A typical example of such rotary storing unit for use in this type of article storing apparatus is described in Japanese Utility Model Laid-Open Publication No. 3-102510, wherein an elongate transport path is formed on a long frame-shaped base by means of a multiplicity of idler rollers arranged thereon, there being provided a plurality of pallets movable on the transport path. The storing unit includes an endless chain trained over a plurality of wheels and extending along the transport path, and a motor for driving the wheels, individual pallets being geared at their respective centers to the endless chain.
In this known arrangement, a control switch is provided on the base side such that the switch is manually operated to actuate the motor to drive the endless chain. As the endless chain is driven, the plurality of pallets are caused to move on the transport path so that a target pallet may be brought to a position opposite to the receiving/discharging station. Thus, loading and unloading of an article relative to the target pallet can be performed by means of a fork lift truck.
However, with the known arrangement, wherein individual pallets are connected at their respective centers directly to link pins of the endless chain, one drawback is that each pallet and the endless chain are disposed close to each other and accordingly each of the wheels must have its top surface positioned in close proximity to a conveyor bearing surface consisting of the article supporting surface of the idler rollers. As such, in order that the wheels may be properly mounted in position, the idler rollers must be arranged in such a way that no idler roller is present at locations where idler rollers may interfere with the wheels. Because of the presence of such locations, therefore, vibrations may occur with pallets being conveyed, with the result that stable and smooth transport of articles cannot be effected. Another drawback is that the elongate transport path, which comprises a pair of straight portions and a pair of rotary portions interconnecting the ends of the straight portions, necessitates pallets being spaced wide apart while in movement on the straight portions in order to prevent the pallets from interfering with one another on the rotary portions, thus involving a considerable dead space.